Coil spring



9, 1966 c. GOLDMEYER ETAL 3,2645% COIL SPRING Original Filed Jan. 23, 1964 ATTO RN EIS.

United States Patent 3,264,660 COIL SPRING Clifford Goldmeyer, Cincinnati, and Thomas J. Dull,

Fairfield, Ohio, assignors to The J. R. Greeno Company, Cincinnati, Ohio, a corporation of Ohio Original application Jan. 23, 1964, Ser. No. 339,638. Divided and this application Oct. 2, 1964, Ser. No. 401,092

3 Claims. (Cl. 5 -351) This application is a division of our parent application Serial No. 339,638, entitled Helical Wrapping Mechanism for Coil Spring Units, filed in the United States Patent Ofiice on January 23, 1964, and assigned to the J.- R. Greeno Company, the assignee of the present application and invention.

Generally speaking, the parent application relates to a machine utilized in the final assembly of coil spring units of the type utilized for mattresses, bed springs and the like. Spring units of this type comprise, in general, parallel rows of coil springs vertically disposed, with the upper and lower terminals of the rows of coil springs joined together at the top and bottom of the spring unit :by helicals which are threaded in corkscrew fashion about adjoining portions of the terminals of the coil springs.

As disclosed in the parent application, the end portions of the transverse helical wires, which are utilized to connect the upper and lower terminals of the rows of coil springs, are also utilized to connect the terminals to the upper and lower border wires which delineate the size and shape of the spring unit. In the past, this connection has required the use of separate connecting devices, such as metal clips or wires, applied in a separate operation to hingedly join the upper and lower terminals of the marginal coil springs to the border wire.

The present application is directed to the improved spring unit, which is fabricated, as outlined above, and also to the method by which it is fabricated, as disclosed generally in the patent application (Serial No. 339,638).

It is therefore one of the primary objectives of the present invention to provide an improved spring unit wherein the helicals, not only connect the top and bottom terminals of the rows of coil springs to one another but also connect the terminals of the marginal coil springs to the border wire at the top and bottom of the spring unit. By virtue of this construction, the use of the separate connecting devices, noted above, is eliminated and the resulting spring unit is improved.

Another objective of the invention, as outline in the parent application, has been to provide an improved method of wrapping the end portions of the helicals about the adjoining portions at the terminals and border wires, comprising the steps of trimming the end portion of each helical, stretching the trimmed end, and of wrapping the trimmed and stretched end portion about the adjoining portions of the terminal and border wire.

In utilizing the wrapping method of this invention, a spring unit is initially assembled by threading the helicals across the terminals of the coil springs, with opposite end portions of the helical projecting outwardly beyond the terminals at opposite sides. Upon being transferred to the wrapping machine, the border wire, the helical and marginal terminal are located and clamped in registry, then the wrapping machine engages the projecting end portion of each helical, trims it, stretches it, then wraps it about the adjoining portions of the terminal and border wire.

A further objective of the invention has been to provide a spring unit, having helicals securing the terminals to the border Wires, wherein the end portion of each helical is wrapped under tension about the adjoining portions of the terminal and border wire, to securely anchor 3,264,660 Patented August 9, 1966 'ice the helical and prevent longitudinal displacement of the helical after prolonged usage of the spring unit.

According to this aspect of the invention, the projecting end portion of each helical is trimmed to a predetermined length (as previously mentioned) prior to the wrapping operation. Upon being stretched, the helical, which extends between the terminal coils and border wire, is in a substantially straight condition, while several turns of the original helical remain unstretched at the end. The unstretched portion is then wrapped about the adjoining terminal and border wire and tightened to provide a clamping effect therebetween. The arrangement is such that the trimmed end of the helical, after the wrapping operation, resides within the confines of the marginal helical and border wire in a concealed position.

Further features and advantages of the invention will be more fully apparent to those skilled in the art from the following detailed description with reference to the drawings.

In the drawings:

FIGURE 1 is a plan, as viewed from above, showing the bottom border wire and lower terminals of a typical coil spring unit embodying the principles of the present invent-ion.

Coil spring Described generally, the spring unit 3 is of the type used in mattresses, bed springs and the like. The spring unit comprises rows of coil springs indicated generally at 6 and joined together at the top and bottom by transverse helicals 7. The spring unit is bounded on all four sides by upper and lower border wires 8.

Each coil spring, in the present example, is generally of hour glass shape, as viewed from the side, with enlarged terminals 1010 at the top and bottom. The terminals 10 lie in level planes and delineate the top and bottom surface of the spring unit. Each terminal 10 includes opposed straight portions 11 which mate with one another to facilitate the application of the transverse helicals 7 which are laced about the adjacent mating straight portions 11 at the topand bottom of each terminal.

In assembling the spring unit 3, prefabricated coil springs 6 are located in row formation, the rows extending transversely across the width of the spring assembly, with the straight portions 11 of the terminals in mating relationship (FIGURE 1). Thereafter, the helicals 7 are located and advanced in cork screw fashion transversely across the spring assembly by means of a helical feeder (not shown). The transverse helicals 7 are thus laced about the mating straight portions 11, thereby to tie the joining rows of coil springs to one another. At completion of the lacing operation, and end portion of each transverse helical, projects outwardly beyond the border wire 8. The projecting portion of the helical subsequently is utilized to tie the marginal terminals 10 to the border wire 8, as explained later.

An automatic machine for fabricating the spring unit to this stage is disclosed in the Greeno et al., Patent 3,045,714. According to conventional practice, by way of example, marginal terminals 10 have been connected to the border wires 8 by threading a longitudinal helical (not shown) upon the upper and lower border wires and terminals. In other instances, the terminals may be joined to the border wires by means of separate clips or individual tie wires.

While the spring assembly fashioned in this manner is highly satisfactory, the transverse helicals 7 have a tendancy to be rotated through flexing of the spring unit after prolonged use, causing an end portion of the helical to project beyond the border Wire at one side of the spring unit or mattress. In order to prevent this action, the ends of the helicals, according to the prior practice, may be deformed in some manner to prevent rotation; By way of example, the patent to John L. Greeno et al., 3,090,407 discloses a machine which forms a loop at opposite ends of the helical to prevent the unscrewing action.

As noted above, the present coil spring utilizes the projecting end portion to tie the terminal coils to the border wire. This arrangement thus eliminates the need for longitudinal border helicals, clips, tie wires or the like, thus bringing about a substantial saving in manufacturing costs and also in material. Moreover,-the end portion of the helical, when wrapped tightly about the terminal and border wire, firmly anchors the helical against axial displacement, thus eliminating the necessity of forming loops at the ends of the helicals, as noted above.

After the helicals 7 have been laced upon the straight portions 11 of the terminals 10, with the opposite end portions projecting outwardly beyond the border wire, each end portion is stretched to provide a relatively straight length, comprising elongated turns, as indicated.at.18.-

The relatively straight length 18 follows generally the curved profile of the terminal 10, then extends generally parallel with the border wire 8." The end portion of 14 of the straight length 18 is then wrapped under tension about the adjoining portions of the terminal to the border wire under clamping engagement. As shown, the wrapped end portion 14 of the helical provides approximately two and one-half turns about the border wire and terminal, wit-h the end 25of the wrapped portion located. inwardly of the terminal 10. Since the end 25 resides behind the terminal 10, the terminal conceals the end of the helical and prevents damage to the fabric covering which is later applied to the coil spring unit.

Having described our invention we claim:

1. .In a coil spring unit having rows. of vertically disposed coil springs including terminals adjoining one another and having a border wire extending aboutthe pe riphery of the spring. unit, the improvement which com prises:

a respective helical threaded :in corkscrew fashion upon the adjoining portions of the terminals of the rows of coil springs, thereby tying said terminals to one another;

the terminals of the coil springs about the=margin of the coil spring unit having portions. in adjoining relationship to said border wire;

the end portion of each. of said helicals, which tie the rows of coil springs to one another, having elongated turns extending generally parallel withthe border wire. from the row of terminals which. is joined together bysaid helical, said elongated turns terminating in an end portion which is wrapped under tension about the border Wire and about the portion.

of the terminal which adjoins the border wire, thereby to secure the terminals to the border wire; the wrapped portion of the helical, which'passes about the border wire and adjoining terminal, providing .a.

upon the adjoining portions of the terminals of the rows ofcoil springs, thereby tying said terminals to one another; the. terminals of the coilsprings about the..margin of the" coil spring unit having-portions in adjoining relationship to said border wire;

the end;portiontof each of said helicals, which tie' the. rows of coil springs-to onezanother, having a sub- 1 stantially straight. portion extending generally parallel with the border wire from the row of terminals which is joinedtogether; by said helical;

said substantially straight portion of .the 'helical Zin clamping engagementbetweenmthe borderwire and adjacent portion of the terminal, thereby to PI'Ee.

vent longitudinal displacement of the helical.

3. In' a coil spring unit having rows of vertically disposed coil springs. including upper and lower terminals. adjoining one. another, and having upper and lower border:

wires extending about the] periphery .of the (spring unit, the improvement which comprises;

a respective helical threaded in corkscrew fashion upon the adjoining'po-rtion of the upper. and lower terminals of the rows of coil isprin'gs, thereby tying said terminals t-o one another;

the terminals of the coil springs about the margin of the coil'spring unit having portions imadjoining relationship to said border wires;

theend portion of each of said helicals,W-hichltiethe rows of coil springs to one another, havinga sub stantially. straight portion extendinggenerallyparallel with the. border wire from the row'of terminals v j which is joined togetherbysaid helical; said substantially straightgportionof'xthe helical dinclo singt an end-portion-which iswrapped under tension about the-end terminalof-an adjacent row of;

coil springs at the margin of the coil spring unit and the adjoining portion :of. the borderwire, thereby tosecure the marginal terminalto the border wire;:

theawrapped portion of the terminal, which passesabout the border-.wire and adjacent terminal, providing a clamping engagement abGtWfifiIlthfi borderwire and adjacent portion :of the terminaLtherebyto pre-v vent longitudinal. displacement of the helical; theend of 'saidiwrapped portion of .the helical being located withinthe confines of the border .wire and terminal.

References Cited by the Examiner UNITED STATES PATENTS 2 2,176,262 10/1939 Kirchner 92.4 2,388,106 10/1945 Wo1ler 140-924 2,644,174 7/1953 Hood 5269 2,708,757 5/1955 Bellgrau 5260 2,885,693 5/1959 Wuest 5260 I CASMIRA. NUNBERG, Primary Examiner. FRA'NKiiB. SHERRY, Examiner.- 

1. IN A COIL SPRING UNIT HAVING ROWS OF VERTICALLY DISPOSED COIL SPRINGS INCLUDING TERMINALS ADJOINING ONE ANOTHER AND HAVING A BORDER WIRE EXTENDING ABOUT THE PERIPHERY OF THE SPRING UNIT, THE IMPROVEMENT WHICH COMPRISES: A RESPECTIVE HELICAL THREADED IN CORKSCREW FASHION UPON THE ADJOINING PORTION OF THE TERMINALS OF THE ROWS OF COILS SPRINGS, THEREBY TYING SAID TERMINALS TO ONE ANOTHER; THE TERMINALS OF THE COIL SPRINGS ABOUT THE MARGIN OF THE COIL SPRING UNIT HAVING PORTIONS IN ADJOINING RELATIONSHIP TO SAID BORDER WIRE; THE END PORTION OF EACH OF SAID HELICALS, WHICH TIE THE ROWS OF COIL SPRINGS TO ONE ANOTHER, HAVING ELONGATED TURNS EXTENDING GENERALLY PARALLEL WITH THE BORDER WIRE FROM THE ROW OF TERMINALS WHICH IS JOINED TOGETHER BY SAID HELICAL, SAID ELONGATED TURNS TERMINAT- 